Macrocephalosaurus ferrugenous = Gilmoreteius (Gilmore 1943) Campanian, Late Cretaceous , ~74 mya, was a basal scerloglossomorph. Derived from a sister to Eolacerta and Tupinambis, Gilmoreteius was a sister to Slavoia and Tianyusaurus and more distantly, Acanthodactylus.

Distinct from Eolacerta, the skull of Gilmoreteius had a taller rostrum/maxilla and had a higher, smaller orbit. The maxilla was ventrally convex. The jugal was more robust and leaned posteriorly. The quadrate was shaped like an inverted L. The lacrimal was considerably shorter. The palatines were smaller. The mandible was deeper. The maxillary teeth had tiny cusps.

The clavicles were broad medially with a large fenestra. The scapula was shorter as were the robust forelimbs. The manual digits were shorter, but retained large unguals.

The ilium had no anterior process. The hind limbs were shorter, but the feet remained elongated. The tibia was less than twice the ilium length. Pedal digit V extended subequal to metatarsal IV.

Gimore CW 1943. Fossil lizards of Mongolia. Bulletin of the American Museum of Natural History 81(4):361-384.

Langer MC 1998. Gilmoreteiidae new family and Gilmoreteius new genus (Squamata Scincomorpha): replacement names for Macrocephalosauridae Sulimski, 1975 and Macrocephalosaurus Gilmore, 1943. Comunicacoes do Museu de Ciencias e Tecnologia 11: 13-18.

Mo J-Y, Xu X and Evans SE 2009. The evolution of the lepidosaurian lower temporal bar: new perspectives from the Late Cretaceous of South China. Proceedings of the Royal Society doi: 10.1098/rspb.2009.0030

Sulimski A 1975. Macrocephalosauridae and Polyglyphanoodontidae (Sauria) from the Late Cretaceous of Mongolia. Palaeontolgia Polonica 33:25-102.

Sulimski A 1984. A new Cretaceous scincomorph lizard from Mongolia. Palaeontologia Polonica, 46, 143–155.

Talanda M 2015. Cretaceous roots of the amphisbaenian lizards. Zoologica Scripta. doi:10.1111/zsc.12138